I want to create a Hive UDF function that returns specific column names based on some value say retreivecol(age).If the age is 20 then return the list of column names to be used in select query like 'name,email,fbuserid,friend list ' etc and if the age is less than 20 return 'name' alone.So I want my HIVE QL query to look like
select retreivecol(age) from User_Data;
The above query just prints the name of the columns like 'name,email,fbuserid,friendslist' etc as opposed to treating them as column names and filtering based on the same.Any pointers are appreciated.
I'm not sure a UDF is the right place to do this, as UDF's simply see the value passed to them, they don't really have access to the whole table structure.
Instead, could you do this in a nested table?
select name,email,id FROM
(
select
name,
if(age < 20, email, NULL) as email,
if(age < 20, id, NULL) as id
FROM mytable
) a
Related
I have 2 tables with the same columns except the second table have one more column, this column is foreign key of the first;
what i want is to make union query;but for union the column must the same; so i want to select all column except for the column distinct;
The easy way is to provide in select all the same column:
$a = Table1::select(['column1', 'column2', 'etc...']);
$b = Table2::select(['column1', 'column2', 'etc...']);
and go with $a->union($b)->get();
but if i have too much column, i end up with so much column to provide in the select function; so what i want is to provide in the query the column that i don't want to retrieve;
i can put protected $hidden in the second table model but for some reason i need this distinct column on some other query;
Get all columns name by Schema::getColumnListing($table);
And computes the intersection of arrays
array_intersect($columnsName1, $columnsName2);
I haven't done it with 2 tables but I am using collections and rejecting certain columns on a similar project:-
$row = Table1::firstOrFail();
$exclude=['column_1', 'column_2'];
return collect(array_keys($row->getAttributes()))
->reject(function ($name) use ($row, $exclude) {
return in_array($name, $row->getHidden())
|| in_array($name, $exclude);
}
);
I have created a classic report region (REGION: REPORT_FILTER_SHOP_TYPE).
That has a SQL below this.
SELECT
ID, SHOP_NAME, SHOP_TYPE, OPEN_YEAR, CITY
FROM SHOP_LIST;
I want to apply a filter to this table. The filter criteria will be selected from the list item. And this page have some lists.
For example, if there is no filter, the SQL right above one. But if the "SHOP_TYPE" and "OPEN_YEAR" are selected, execute the SQL below.
SELECT * FROM (
SELECT
ID, SHOP_NAME, SHOP_TYPE, OPEN_YEAR, CITY
FROM SHOP_LIST
) S
WHERE S.SHOP_TYPE = 'BOOKSTORE' AND S.OPEN_YEAR <2010;
I can now create the compose SQL text from selected list items.
What do I need to set to display this result in REPORT_FILTER_SHOP_TYPE?
Well, most probably not like that; why using parameters on a page if you hardcode some values into report's query? Use parameters!
Something like this:
SELECT id,
shop_name,
shop_type,
open_year
FROM shop_list
WHERE ( shop_type = :P1_SHOP_TYPE
OR :P1_SHOP_TYPE IS NULL)
AND ( open_year < :P1_OPEN_YEAR
OR :P1_OPEN_YEAR IS NULL);
Currently I am trying to find all the unique indexes defined in a table which are NOT NULL for Oracle database. What I mean by that is, Oracle allows creating unique indexes on columns which are even defined as NULL.
So if my table has two unique indexes, I want to retrieve the particular unique index which is having all the columns having the NOT NULL constraints.
I did come up with this query:
select ind.index_name, ind_col.column_name, ind.index_type, ind.uniqueness
from sys.dba_indexes ind
inner join sys.dba_ind_columns ind_col on ind.owner = ind_col.index_owner and ind.index_name = ind_col.index_name
where ind.owner in ('ISADRM') and ind.table_name in ('TH_RHELOR') and ind.uniqueness IN ('UNIQUE')
The above query is giving me all the unique indexes with the associated columns, but I am not sure, how should I join the above query with ALL_TAB_COLS which has the NULLABILITY data for all the columns of a table.
I tried joining this table with indexes and tried subquery as well, but not getting appropriate results.
Hence, would request you to please comment on same.
Analytic functions and inline views can help.
The analytic functions let you return detailed data but also create a summary on that data, based on separate windows. The detailed results include index owner, index name, and column name, but the counts are only per index owner and index name.
The first inline view joins the three tables, returns the detailed information, and has analytic functions to generate the count of all columns and the count of all nullable columns. The second inline view only selects rows where those two counts are equal.
--Unique indexes and columns where every column is NOT NULL.
select owner, index_name, column_name
from
(
--All relevant columns and counts of columns and not null columns.
select
dba_indexes.owner,
dba_indexes.index_name,
dba_tab_columns.column_name,
dba_tab_columns.nullable,
count(*) over (partition by dba_indexes.owner, dba_indexes.index_name) total_columns,
sum(case when nullable = 'N' then 1 else 0 end)
over (partition by dba_indexes.owner, dba_indexes.index_name) total_not_null_columns
from dba_indexes
join dba_ind_columns
on dba_indexes.owner = dba_ind_columns.index_owner
and dba_indexes.index_name = dba_ind_columns.index_name
join dba_tab_columns
on dba_ind_columns.table_name = dba_tab_columns.table_name
and dba_ind_columns.column_name = dba_tab_columns.column_name
where dba_indexes.owner = user
and dba_indexes.uniqueness = 'UNIQUE'
order by 1,2,3
)
where total_columns = total_not_null_columns
order by 1,2,3;
Analytic functions and inline views are tricky but they're very powerful once you learn how to use them.
I have a model User that has many Orders. Orders have many products, with the pivot table order-product. I don't want to preload and iterate through the orders if at all possible.
I need to return users where
signed_date === true on User
order_date on Order is after signed_date on User
order-product shows product hasn't been paid
I am failing on number 2.
In the following code, the first query within whereHas is wrong. I don't know how to reference the signed date of the user from within the where has. If I was iterating through users in a collection I could do something like ($query) use $user, but how do I do this without preloading all the users?
return User::whereNotNull('signed_date')
->whereHas('orders', function ($query) {
$query->where('order_date', '<=', 'user.signed_date');
$query->whereHas('products', function ($q) {
$q->where('paid', false);
});
})
->get(['id','fname','lname', 'title', 'signed_date']);
I would like to use eloquent if possible. If that is not possible, I would be happy for tips in solving this problem using the query builder/sql.
The Eloquent query builder has a special function called whereColumn('a', '<=', 'b') to compare columns instead of a column against a value. Using this function instead of a normal where() is necessary because of the way the query builder builds the actual query. You need to let the query builder know that you are going to pass a column name instead of a value for proper escaping and formatting of the query string.
Anyway, it seems you can also pass column names prefixed with a table name to the function, allowing you to compare columns across tables:
$query->whereColumn('orders.order_date', '<=', 'users.signed_date')
This works because you are using whereHas() in your query. Your query basically gets translated to:
SELECT id, fname, lname, title, signed_date
FROM users
WHERE signed_date NOT NULL
AND EXISTS (
SELECT 1
FROM orders
WHERE orders.order_date <= users.signed_date
AND EXISTS (
SELECT 1
FROM products
WHERE paid = 0
)
)
It might actually be not necessary at all to use the table name together with the column name in whereColumn(). But in case you'll ever add a column named the same on another table, the query might break - so IMHO it is good practice to use the table name in custom queries.
By the way, the reason this will not work together with with('relationship') is that this function results in an additional query and you obviously cannot compare columns across queries. Imagine the following:
Order::with('user')->take(5)->get();
It will be translated into the following:
SELECT *
FROM orders
LIMIT 5
SELECT *
FROM users
WHERE id IN (?, ?, ?, ?, ?)
where the five ? will be the user_ids of the orders. If the first query returns multiple rows with the same user_id, the amount of rows fetched from the users table gets reduced of course.
Note: All the queries are only examples. Might be that the query builder builds different queries based on the database type and/or escapes them differently (i.e. column names in backticks).
my table looks like this:
If the field name contains cost or quantity for the same lineItemIds, I have to display the result as:
cost is changed from 8*1=8
(fromVal*fromVal) to 9*6=54
(toVal*toVal) for itemID 123.
any help will be appreciated.
SELECT tc.LINE_ITEM_ID ITEM_ID,
tc.FROMVAL COST_FROMVAL,
tq.FROMVAL QTY_FROMVAL,
(tc.FROMVAL*tq.FROMVAL) PROD_FROMVAL,
tc.TOVAL COST_TOVAL,
tq.TOVAL QTY_TOVAL,
(tc.TOVAL*tq.TOVAL) PROD_TOVAL,
FROM
(SELECT LINE_ITEM_ID,
FROMVAL,
TOVAL,
FROM table
WHERE FIELDNAME = 'cost') tc
JOIN (SELECT LINE_ITEM_ID,
FROMVAL,
TOVAL,
FROM table
WHERE FIELDNAME = 'quantity') tq
ON tc.LINE_ITEM_ID = tq.LINE_ITEM_ID
I would look into using product aggregate functions. You'll have to compile them yourself though, Oracle doesn't include them as system functions. http://radino.eu/2010/11/17/product-aggregate-function/
If it's just for this one case where cost or quantity are used, then you could also just use subqueries, or temporary transaction based tables.
I'd provide you with a query example, but unfortunately don't have an Oracle instance accessible presently.